Cortical Somatosensory Processing in Humans

我的研究计划的中心主旨是描述人类躯体感觉皮质的时空组织。 为此，我使用功能磁共振成像(FMRI)对人脑中处理体感信息的皮质区域进行了功能性定位。例如，我研究了手指在人体体感皮质中的表征(即体感躯体操作)，并探索了触觉运动后效的神经基础。我还开发了心理物理技术来研究人类的触觉工作记忆。最近，我开发了触觉工作记忆的计算模型。 在目前的提案中，我将使用超高场fMRI(7T)、高密度事件相关电位(ERP)以及计算建模来继续这些研究。功能磁共振成像将允许对空间组织进行非常详细的研究，而事件相关电位将使研究功能磁共振成像所调查区域之间的时间关系成为可能。我将通过研究触觉刺激的空间(例如位置)和时间(例如刺激频率和刺激之间的时间关系)方面如何调节这些区域的活动来继续研究躯体感觉皮质和相关顶区的功能特征。我还将继续进行正在进行的心理物理触觉工作记忆实验，目的是将这种技术引入神经成像环境(包括功能磁共振成像和事件相关电位)。最后，我将继续研究触觉工作记忆的计算模型 这项资助中概述的工作不仅将有助于我们理解在触觉刺激过程中人类顶叶和相关皮质中产生的信号的性质(这些信号的皮质来源及其时序关系)，而且它还将提供有关涉及体感知觉的不同皮质区域如何相互作用以及在触觉工作记忆任务期间这些大脑区域如何保持这些信号的信息。

The central thrust of my research program is to characterize the spatial and temporal organization of human somatosensory cortex. To this end, I have used functional magnetic resonance imaging (fMRI) to functionally localize cortical regions in the human brain that process somatosensory information. For example, I have examined the representation of the fingers in human somatosensory cortex (i.e., somatosensory somatotopy) and probed the neural substrates of the tactile motion aftereffect. I have also developed psychophysical techniques to investigate human tactile working memory. Most recently, I have developed computational models of tactile working memory. In the current proposal I will use ultra-high field fMRI (7T), high-density ERP (event-related potentials), as well as computational modeling to continue these investigations. fMRI will allow for highly detailed study of spatial organization and ERP will make it possible to study the temporal relationships between the regions investigated with fMRI. I will continue examining the functional characteristics of somatosensory cortex and related parietal regions by investigating how spatial (for example, location) and temporal (for example, frequency of stimuli and timing relations between stimuli) aspects of tactile stimulation modulate activity in these regions. I will also continue ongoing psychophysical tactile working memory experiments with the aim of importing such techniques into a neuroimaging context (both fMRI and ERP). Finally, I will continue to investigate computational models of tactile working memory The work outlined in this grant will contribute not only to our understanding of the nature of the signals (the cortical origins of these signals and their timing relationships) arising within human parietal and associated cortex during tactile stimulation, but it will also provide information about how the various cortical regions involved in somatosensory perception interact and how such signals are maintained in these brain regions during tactile working memory tasks.